Heisman Trophy recipients typically have outstanding performances in the most important games. By that criterion, Oregon quarterback Dennis Dixon has to be the leading candidate after leading the Ducks to a 35-23 victory over Arizona State last Saturday.

By the same token, struggling in a big game can derail a players' candidacy, which is why Boston College quarterback Matt Ryan can no longer be considered among the top contenders after throwing multiple interceptions in an upset loss to Florida State.

Of course, there still is ample opportunity for everybody, including Ryan, to enhance their bids with big performances. Just look at Arkansas tailback Darren McFadden, who is back among the top contenders after a record-tying rushing performance against South Carolina.

1. Dennis Dixon, Oregon, QB: He threw four touchdown passes to lead the Ducks to victory in a matchup of highly ranked teams. That may put him in the position where the Heisman is his to lose.

2. Tim Tebow, Florida, QB: He passed for three touchdowns and ran for two in a victory over Vanderbilt. That marked the sixth game this season Tebow has accounted for at least four touchdowns.

3. Darren McFadden, Arkansas, RB: The preseason favorite has to make a big move at the end of the season, and he certainly made one in last week's victory over South Carolina. Although McFadden does have a couple of pedestrian games, his SEC record-tying 321 yards last week re-establishes him as a serious contender.

4. Chase Daniel, Missouri, QB: Daniel threw five touchdown passes in an unexpected blowout of Colorado. He has thrown for at least 200 yards in every game this season and ranks fourth nationally in passing.

5. Matt Ryan, Boston College, QB: Ryan threw for more than 400 yards against Florida State last week, but three costly interceptions drop him down the list.

Olin Buchanan is a Heisman trophy voter and the senior college football writer for Rivals.com. He can be reached at olin@rivals.com.